Preheat your oven to 400°F (200°C) and line a large rimmed baking sheet with parchment paper for easy cleanup.
Cut the chicken breast into uniform 1-inch cubes and place them into a large mixing bowl.
Add the broccoli florets, sliced carrots, and chopped red bell pepper to the bowl with the chicken pieces.
Drizzle the extra virgin olive oil and fresh lemon juice over the chicken and vegetables.
Sprinkle the dried oregano, garlic powder, sea salt, and black pepper evenly over the mixture.
Toss everything together with a large spoon or clean hands until every piece is well-coated in the oil and seasonings.
Spread the mixture in a single layer on the prepared baking sheet, ensuring there is space between the pieces for even roasting.
Roast in the center of the oven for 18 to 22 minutes, or until the chicken reaches an internal temperature of 165°F and the vegetables are tender and lightly browned.